Using couple-level, panel data, we examine how cohabitors' economic circumstances, domestic contributions, gender attitudes, and feelings about domestic equity affect whether they continue to cohabit, separate, or marry. We address whether the contemporary trend toward delayed marriage may be influenced by women's and men's preferences for a marital partner who will share parallel employment and homemaking duties, the difficulty in fulfilling that preference, and uncertainty about gender roles and personal relationship entitlements. Thus, we test two competing models of mate selection, traditional (sex-specialized) and egalitarian (collaborative), and evaluate whether couples' attitudes about gender equity complicate these two models. Our findings primarily support the sex-specialized model, with women's housework and men's earnings associated with higher odds of marriage, and cohabiting men's mate selection strategies seemingly consistent with an exchange of breadwinning for homemaking. Partial support for the collaborative model shows that men's egalitarian attitudes are associated with higher odds of marriage, while the interaction between women's time spent in housework and earnings is associated with higher odds of separation. Given that cohabitors have higher odds of separation if the female partner is more egalitarian than the male partner and that women's perceptions of unfairness to self about housework do not affect union outcomes, we conclude that cohabitors generally use a breadwinner–homemaker framework for evaluating partners' economic and domestic contributions as mate selection criteria.